Timer value
15s NOTE 7 NOTE 8 In WB-S1/CE mode, 77s NOTE 17
Source: 3GPP TS 24.301 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
3GPP Scout / Reference / EPS NAS timers / T3430
TS 24.301NAS timer
Timer T3430: EPS mobility management, UE side
In plain words
The UE starts T3430 after sending TRACKING AREA UPDATE REQUEST. When T3430 expires, the UE starts T3411 or T3402 as described in clause 5.5.3.2.6.
Our summary of the spec text quoted below.
What the spec says
Started when
TRACKING AREA UPDATE REQUEST sent
Source: 3GPP TS 24.301 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Stopped when
TRACKING AREA UPDATE ACCEPT received TRACKING AREA UPDATE REJECT received
Source: 3GPP TS 24.301 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
On expiry
Start T3411 or T3402 as described in clause 5.5.3.2.6
Source: 3GPP TS 24.301 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
State
EMM-TRACKING-AREA-UPDATING-INITIATED
Source: 3GPP TS 24.301 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
How this page was made
3GPP Scout built this page from TS 24.301 V20.1.0 as indexed on 2026-10-15. The quotes are copied from the spec, and code checks each one against the stored text and the 3GPP archive file before publishing. The plain-words line was written by an AI model (GPT-6 Sol) and checked against the quotes by a second AI model from another company (Claude Opus 5.5). The official 3GPP text governs.